Prior research on risk factors for posttraumatic stress symptomatology (PTSS) in war-exposed Veterans has revealed both direct and indirect mechanisms of risk that span predeployment, deployment, and postdeployment timeframes. The aims of the present study were to identify the mechanisms through which previously documented risk factors contribute to PTSS in a national sample of 579 female and male Veterans deployed to Afghanistan for Operation Enduring Freedom (OEF) or to Iraq for Operation Iraqi Freedom (OIF), as well as to examine the extent to which results mirror associations observed among Vietnam Veterans (King, King, Foy, Keane, & Fairbank, 1999). Consistent with conservation of resources (COR) theory (Hobfoll, 1989, 2001), findings indicated that PTSS is accounted for by multiple chains of risk, many originating in predeployment experiences that place Veterans at risk for additional stress exposure, and foretell difficulty accessing resources in the face of subsequent stressors. Importantly, the majority of previously documented mechanisms were replicated in this study, suggesting key pathways through which risk factors may contribute to PTSS across different Veteran populations. Results also revealed a number of novel risk mechanisms for OEF/OIF female Veterans, particularly with respect to the role of deployment family relationships in risk for PTSS.